Research Article and conservation ot the South Atrican tiora Page 1 of 10

Taxonomic research priorities for tiie conservation AUTHORS: of the South African flora Lize von Staden' Domitilia Raimondo' Anisha Dayaram' Taxonomic revisions, monographs and floras are the most important, and often the only source of data for assessing the extinction risk of , with recent revisions contributing to more accurate assessments. AFFILIATION: The recently completed Red List of South African plants involved an overview of the taxonomic literature threatened Species pertaining to the South African flora, providing an opportunity to identify critical gaps in taxonomic coverage. Programme, South African In this study we identified taxonomic research priorities for effective conservation of South African plants. National Biodiversity Institute, Pretoria, South Africa Priorities were identified at level, according to time since last revision, level of endemism, collecting effort, proportion of taxa included in revisions, and specimen identification confidence. Although the results CORRESPONDENCE TO: indicate that 62% of the flora has been recentiy revised, revisionary taxonomic output has declined drastically, Lize von Staden particularly in the past 10 years. This decline is a result of a decrease in revisionary productivity per taxonomist and not a resuit of a decline in the number of working taxonomists. The family is the top priority EMAIL: for taxonomic research with 55% of taxa in need of revision, followed by Hyacinthaceae with 34% of taxa not [email protected] yet revised. Ericaceae, Euphorbiaceae, Rutaceae, Malvaceae, and Acanthaceae are also priorities with over 30% of taxa last revised before 1970. We recommend the reinstatement of the Flora of Southern POSTAL ADDRESS: Threatened Species Programme, Africa project in an online format in order to centralise South Africa's existing taxonomic information and South African National reinvigorate revisionary taxonomic study. This project wili allow South Africa to fulfii its commitments to the Biodiversity institute. Private Convention on Biodiversity by actiieving Target 1 of the Global Strategy for Conservation. Bag X101, Pretoria 0001, South Africa

OATES: Introduction Received: 16 iVlar 2012 The first comprehensive Red List of fhe indigenous vascular plants of South Africa was published in 2009.^ The Red List project involved the evaluation of more than 20 000 piant taxa (species, subspecies and varieties) against Revised: 28 Aug. 2012 scientifically based, quantitative criteria for the determination ot extinction risk.^'^ These criteria demand data on Accepted: 26 Sep. 2012 population size, rates of population decline, range size, number and location ot subpopulations, and knowledge ot threats, ecology and bioiogy of species. Such data are avaiiable for only a smaii number of well-studied species; KEYWORDS: however, the criteria are flexible enough to allow estimation and inference of criteria parameters in the absence threatened species; lUCN Red of high-quality observation data.^ For exampie range size may be estimated based on georeferenced herbarium List; taxonomic revisions; specimens and popuiation decline may be inferred if the extent of a species' habitat is known to be decreasing as taxonomic productivity; Globai a result ot human impact. Strategy for Plant Conservation There is, however, a core body of information without which risk of extinction cannot be assessed: knowledge HOW TO CITE: of the distribution range, habitat requirements and the bioiogy of the species. This basic information is obtained Von Staden L, Raimondo D, primarily from the taxonomic literature. Taxonomy as a science is the synthesis of data derived from collected Dayaram A. Taxonomic research specimens to define and circumscribe species and their distributions. While taxonomic study is not able to supply priorities forthe conservation all the data required for Red List assessments, it allows for further study of biodiversity by providing a means to of the South African flora. S name and classify bioiogical observations. Theretore, groups of species that are taxonomicaiiy weii studied are AfrJSci. 2013;109(3/4),Art. also generally better known biologically, while those that are in need of taxonomic revision tend to remain poorly #1182,10 pages, http://dx.doi. known species. org/10.1590/sajs.2013/1182 The comprehensive assessment of Soufh African plants was significantly aided by recent, comprehensive taxonomic monographs, revisions, fioras and, to a lesser extent, conspectuses. Recent treatments mean that the majority of taxa in a group are well defined, and their distributions and habitats are accurately circumscribed. In addition, groups with recent taxonomic treatments are most often better coliected, which means that herbarium specimens are a more reliable indicator of the relative abundance of taxa, and there is higher confidence that specimen identifications are correct." On the other hand, taxa in genera and families with no or very outdated revisions were extremely difficuit to evaluate, and many had to be assigned to the category 'Data Deticienf , indicating that they are suspected to be at risk of extinction, but sufficient data to apply the quantitative criteria is lacking. Confidence in the accuracy of the assessments for taxa in such groups is also very low,^ and one study has shown that 75% of Red List assessments completed in the absence of revisions were incorrect categorisations, when compared to reassessments of the same taxa after the compietion of revisions." In this study we used the bibliography of over 3000 taxonomic literature references that was compiled as part of the South African plant Red List project to evaiuate the state of revisionary taxonomic coverage of the South African flora, identify knowledge gaps and set research priorities, as well as to analyse recent taxonomic output to assess the capacity of South African taxonomic researchers to meet research needs towards achieving Target 1 of the Global Strategy for Plant Conservation (GSPC).

History of plant taxonomy In South Africa ©2013. The Authors. The first South African plants were described and iiiustrated in European herbáis in the 17th century,' but the first Published under a Creative attempt to catalogue, describe and classify all known plants of the Cape fiora was compieted by the Swedish Commons Attribution Licence. botanist Carl Peter Thunberg between 1807 and 1820.' This achievement was followed by the Fiora Capensis

Soutii African Journai of Science Voiume 109 \ Number 3/4 http://www.sajs.co.za 48 March/Aprii 2013 Researeh Artiele Taxonomy and conservation of the South African flora Page 2 ot 10 series, whieh was published in seven volumes between 1859 and 1925 Atrica requires consolidating taxonomie intormation trom seattered and eontained treatments ot more than 11 000 taxa. publications, updating outdated intormation and toeusing on addressing gaps in the knowledge ot our tlora. As the Red List projeet relied so As the knowledge ot the riehness and diversity ot the South Atriean tlora heavily on taxonomie literature, it necessitated a near-comprehensive was understandably still very limited in the late 19th eentury, the series overview ot the taxonomie literature pertaining to the South Atrican tlora, beeame out ot date very quiekly, and in the 1960s the Flora ef Southern and theretore provided a unique opportunity to identity critical gaps in Africa series was established by the state-tunded Botanieal Researeh taxonomie eoverage ot the tlora. Institute (now the South Atriean National Biodiversity Institute), with the aim ot eompleting a taxonomie treatment ot the plants ot South Atriea, Namibia, Botswana, Swaziland and Lesotho by 2000.^* Revisions were Methods completed by statt ot the institute, but contributions trom other local and international researchers were also aeeepted. Progress has been slow,' Literature review however, and to date tlora treatments ot only 402 genera, representing All vaseular plant genera with three or more taxa indigenous to South 17% ot the indigenous South Atriean taxa, have been Atrica (923 genera in total), representing 94% ot the tlora, were included completed (including 18 shorter 'FSA contributions' published in the in the analysis. For each genus, all taxonomie revisions (including tlora journal Bothaiia), and no new sections have been published since 2005. treatments) were recorded in a database, together with the date ot publication, in order to determine the most recent date ot taxonomie In the meantime many local and internationally based researchers have revision tor eaeh taxon. As taxonomie treatments ean take many torms completed revisions and monographs ot South Atriean plant tamilies (e.g. monographs, revisions, synopses and conspectuses), and there is and genera independently ot the Flora of Southern Africa project. no strict detinition ot what must be included in each ot these types ot These publications are valuable contributions to the knowledge ot the treatments, tor the purposes ot this study, any treatment that contained South Atrican tlora, but untortunately these independent revisions are an identitication key to species level, scientitic names listed together scattered across many scientitic journals and various other publications, with their protologue citations, type specimens, and synonyms, were making them ditticult to access, particularly tor users outside the included. Partial revisions, such as tor subgenera and subcountry academic system. geographical regions, were also included, but short taxonomie notes, such as revisions ot species complexes and descriptions ot new taxa, were excluded. Although such shorter publications contribute to the Taxonomy and conservation ot ttie South Atrican tlora bulk ot taxonomie literature available on the South Atriean tlora, it has The ettective conservation ot South Atrica's indigenous plants is a been noted that there is a trend to publish taxonomie notes instead signiticant challenge. South Atrica has the world's richest temperate ot complete revisions or monographs, particularly when revisionary tlora,'" with ca. 20 700 indigenous vascular plant taxa in 1890 genera and research is undertaken as part ot postgraduate studies, with the tull 252 tamilies. Eight tamilies comprising 349 genera - 67% ot plant taxa - revision remaining unpublished in a dissertation. For this reason, are endemic to South Atrica. In addition. South Atrica is one ot only two whether a revision is published or unpublished was also recorded, countries in the world whose borders contain three globally recognised in order to quantity what proportion ot the tlora is attected by this hotspots ot biodiversity," comprising areas with exceptionally high trend. New species descriptions are an important contribution to levels ot species diversity and endemism that are also under signitieant the documentation ot biodiversity; however, it these descriptions are threat trom human impaet on the environment. With the iimited resourees published independently ot revisionary studies they do not contribute alloeated to eonservation, it is essential that well-intormed priorities are to a better understanding ot taxonomie groups that may otherwise be in set to ensure ettective channelling ot conservation ettorts. Red Lists are need ot revision," and henee were not ineluded in the analysis. primarily used to guide priority setting in a wide range ot conservation initiatives in South Atrica, and because they are reliant on adequate For partial revisions, and those that were outdated, the taxa ineluded in taxonomie treatments, a sound taxonomie baseline is needed to avoid the revision were reeorded. For reeent, tull revisions, the assumption the misdirection ot scarce resources resulting trom a lack ot knowledge was made that all indigenous South Atriean taxa were treated. A eut-ott ot species, their distributions and habitat requirements. date ot 1970 was chosen to ditterentiate revisions considered recent enough to aid Red List assessments trom those considered outdated. Increased international tocus on stemming the loss ot biodiversity, Taxonomie treatments published since the 1970s usually contain starting with the Rio Earth Summit ot 1992 where the United Nations distribution and habitat intormation (including distribution maps), whieh Convention on Biological Diversity (CBD) was ratitied, has led to a is the most eritieal intormation needed tor the evaluation ot extinetion renewed recognition ot the importance ot the science ot descriptive risk, while earlier publieations tend to be limited to morphologieal (alpha) taxonomy as the basis without which the ettective conservation descriptions and cited specimens, whieh means that speeies' habitat ot biodiversity cannot be achieved.''^'^" As a result, numerous initiatives requirements need to be interred. It is reeognised that some revisions and projects aimed at increasing support tor taxonomie researeh through eompleted prior to 1970 may still be taxonomically sound and sutticient tunding and eapacity building have been established,'^"^" and yet, at the tor identitying specimens. Treatments predating 1970 are thus only same time, the decline ot taxonomie researeh worldwide eontinues.''^'-^" considered outdated trom a conservation assessment perspective. The GSPC is a programme ot the CBD aimed at providing a tramework Taxa were categorised as tollows: (1 ) taxa that have never been included tor a coordinated approach to plant conservation through 16 outcome- in any taxonomie revisions, (2) taxa that have not been revised since oriented targets. As a party to the CBD, South Atrica has adopted the the Flora Capensis series, (3) taxa that were last revised betöre 1970 GSPC tor implementation at national level. The importance ot a strong and (4) taxa with recent enough revisions to support contident Red List taxonomie basis tor plant eonservation is reeognised in GSPC Target 1, assessments. This last category was turther divided into taxa tor which whieh in the seeond phase (2010-2020) ot the implementation ot the the most recent revisions were published or unpublished. strategy has been revised trom 'a working list ot known plant speeies eompleted by 2010' to 'an online tlora ot all known plants available Evaluation ot taxonomie coverage ot the tlora by 2020'. This change was made because the compilation ot a global checklist ot plant species was largely successtully achieved, and The proportion ot the South Atrican tlora in need ot taxonomie revision because checklists alone are not sutticient to support plant conservation: was then quantised by evaluating the number ot taxa in each ot the intormation on geographic distribution, identitication tools, pictures and tour categories as a proportion ot the total number ot taxa ot the South basic descriptions are also needed.^' Atrican tlora. These tour categories were also used to indicate which ot South Atrica's 20 largest plant tamilies, together representing 75% ot the This new target presents a challenge because South Atrica lags behind tlora, are most in need ot taxonomie study, by highlighting those plant many other regional tlora projects ot the world, which are either already tamilies in which a large proportion ot the taxa tall within Categories 1 to complete or nearing completion.^ Achieving this target tor South 3. For smaller tamilies, priorities are best set at the genus level.

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Setting priorities Specimen identification confidence Although broad areas in need ot research focus were identified at the Even though some genera may have revisions, current treatments may tamiiy level, taxonomic revisions are typicaiiy undertaken at the genus be inadequate, resuiting in a number of unidentifiable specimens.^^ level. Data compiied tor the first section of this study were theretore in genera with outdated revisions, unidentitied specimens may also then used to prioritise genera most urgently in need of taxonomic indicate the existence ot unrecognised taxa, and a need for taxonomic revision. Priorities were set according to scores tor a number ot factors revision. PRECIS specimen data were used to identity genera with high that indicate a need tor taxonomic revision, in addition to data on when proportions ot unidentified specimens or specimens identitied with iow genera were iast revised, as some oider revisions may stiii be otherwise contidence, in order to give such genera higher research priority. adequate in their delimitations and coverage of taxa. These factors were: endemism, data deticiency, collecting effort, proportion ot genus revised and specimen identification contidence. The overaii priority score was Date last revised caicuiated by averaging the scores for each factor: all tactors considered Genera were prioritised according to the date of their most recent were given equal weight. Genera were then ranked according to their revision, in instances where genera had been partially revised, or where overaii score, from highest to iowest priority. taxonomic changes had resuited in the combining ot a number ot smaller genera that were independentiy revised previously (such as Erica and Endemism Moraea), an exact date ot iatest revision for the genus as a whole couid Endemic genera and famiiies represent South Africa's unique contribution not be pinpointed, and in such cases an average otthe most recent date to the giobal flora, and shouid be a priority for iocai researchers.^'^ Genera ot revision tor each taxon in the genus was caicuiated. were prioritised according to the proportion ot the giobai number ot As values tor the other factors were scaied such that higher numbers recognised taxa per genus that are endemic to South Atrica, with highest indicated higher priority, the number of years since the average ot the priority given to endemic and near endemic genera. most recent date ot revision tor each taxon was used to score each genus. No score was recorded for genera with no revisions, and total Data deticiency scores were then caicuiated as an average ot the scores of the tive A high proportion ot taxa ciassified as Data Deficient in the Red List ot other tactors. South African plants is an indication of a lack of sufficient knowledge of a genus, and need for further study. Genera were prioritised according The tactors anaiysed were seiected specifically to highiight research to the proportion of taxa in each genus ciassitied as Data Deticient, needs in terms of the tocus of this study: to increase the revisionary and highest priority assigned to genera with the highest proportion ot coverage ot the South Atrican fiora in order to improve contidence in data deficiency. Red List assessments. There are many other tactors, such as economic importance or traditionai or cuiturai vaiue, that couid aiso be considered, Collecting effort and which would provide different priorities. In pooriy coliected genera, it is very difficuit to discern whether a iack It is recognised that some ot the priority genera highlighted through this of herbarium specimens indicates genuine rarity (and theretore higher process may already be under revision, it was not possible for this study potentiai extinction risk), or a iack of coiiecting effort, it has been to inciude a survey of current taxonomic studies, and it was considered shown that at ieast 15 herbarium specimens are needed to reach 95% more important to iist aii priorities as a means to encourage ongoing accuracy in distribution range size estimates tor piant species, and with study. Furthermore, many studies ot genera noted to be under revision in tewer than 5 specimens, iess than 10% ot conservation assessments a previous anaiysis ot the fiora^' were never pubiished. are correct.^' Coiiecting effort is closely iinked to taxonomic study, as research stimuiates increased coiiecting of a particuiar group under study. Taxonomically problematic genera are typically pooriy Taxonomic output coliected.^" Herbarium specimen data encoded in the South African For aii revisions analysed, aii authors, as well as the institutional Nationai Biodiversity institute (SANBi)'s Nationai Herbarium, Pretoria affiiiation of the senior author, were recorded in one ot the foiiowing Computerised information System (PRECiS) database were anaiysed categories: (1 ) SANBi - aii researchers based at any one ot the herbaria to identify genera with high proportions of taxa with tive or fewer or botanicai gardens associated with this state-tunded research institute, specimens, and these were aiiocated higher research priority. which has existed under various names (Botanicai Research Institute, Nationai Botanicai Gardens and National Botanicai Institute) over the Taxon coverage of revisions past 50 years: (2) South Atrican Universities - academic statt as weii New taxa are otten described and published independently ot revisions. as researchers associated with university-based herbaria such as Boius Excessive independent publications decrease the vaiue ot existing Herbarium (University ot Cape Town) and Bews Herbarium (University ot revisions tor circumscribing and identitying taxa, as newiy recognised KwaZuiu-Natai): (3) researchers from internationai institutions, inciuding taxa are not incorporated into frameworks for identitication such as herbaria, botanicai gardens and universities and (4) independent dichotomous keys, which can only be produced as part ot broadly researchers, i.e. part-time or amateur botanists or indigenous piant comparative studies such as revisions," or otherwise do not contribute enthusiasts trom a horticuiturai background. to a better knowledge and understanding ot genera that may be in need of revision. These data, together with counts ot the number ot taxa revised in each pubiication and the date ot pubiication, ailowed the calculation ot the In other instances, genera may have recent revisions, but the pubiications contribution ot different institutions to taxonomic revisionary output, as cover only a subset ot the South Atrican taxa. Such genera may be given weii as detection ot changes in output over time. The contribution of low priority it only the date ot most recent revision is considered, in individuai researchers over time was aiso anaiysed to quantify changes order to highiight such genera, as weii as those requiring synthesis, a in capacity and productivity. revision taxon coverage score was caicuiated tor each genus, with the number of South Atrican taxa included in the revision(s) for the genus Revisionary productivity was caicuiated as the number of taxa revised as a proportion of the currentty recognised number of South African per researcher per decade. For multi-authored pubiications, each author taxa. Higher priority was given to genera where a high proportion ot was given credit in terms ot number ot taxa revised by dividing the totai recognised taxa are not treated within existing taxonomic revisions. number ot taxa revised in the pubiication by the number ot authors.

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Results priority genera in the Aizoaceae, but 13 of the 16 South Atrican plant genera without any revision are also in the Aizoaceae (Table 2). state of South African plant taxonomy Table 2: South Atrican plant genera which to date have had no taxonomic The analysis revealed that 62% ot the South Atrican tlora has been revision, not even partial revisions, in order ot priority trom revised recently enough to support conservation assessments (Figure highest to lowest 1), but that 8% ot recent treatments (5% otthe tlora) remain unpublished. A total ot 13% ot the tlora has no taxonomic revision and 6% ot taxa has Genus Family Number ot taxa Endemism to not been revised since the Flora Capensis series, meaning that 19% of indigenous to South Atrica the tlora is urgently in need of taxonomic research. South Atrica Delosperma Aizoaceae 142 Near endemic 5% • Recently revised Arenifera Aizoaceae 4 Endemic 19% Dicrocaulon Aizoaceae' 7 Endennic • Recently revised, Hereroa Aizoaceae 27 Near endemic but unpubiished Antimima Aizoaceae 96 , Near endemic 6° D Revision Rhinephyllum Aizoaceae 10 Endemic outdated Corpuscularia Aizoaceae 8 Endemic D Flora Capensis Chasmatophylium Aizoaceae 8 Near endemic 57% ^^^^^^H only Peersia Aizoaceae 3 Endemic ^^ w D No revision Rabiea Aizoaceae 6 Near endemic Schwantesia Aizoaceae 8 Near endemic Figure 1: Overview ot the taxonomic status ot the South Atrican tlora, Nananthus Aizoaceae 6 Near endemic showing the proportion ot taxa (species and subspecitic ranks) Aizoaceae 7 Endemic that have been recentiy revised, those with outdated (older than 1970) revisions, those not treated since the Fiora Capensis Chamarea Apiaceae 5 Near endemic series and those with no revision. Bassia Chenopodiaceae 3 Widespread Ceraria Rortulacaceae 3 Near endemic Research priorities for conservation The succulent family Aizoaceae, commonly known as 'vygies' or 'ice The Aizoaceae is South Africa's second most diverse plant family, piants', is considered the top priority tor taxonomic research (Table 1), and is divided into tour subtamilies. Two ot these subtamilies, with 52% of taxa in need of revision. Not only are 16 ot the top 20 highest Mesembryanthemoideae and Ruschioideae, are near endemic to

Table 1 : South Atrica's 20 largest plant tamilies, in order ot priority (highest to lowest) in terms ot taxa in need ot revision, with the top priority genus within each tamily

Family Number ot taxa indigenous to Proportion ot recognised taxa Proportion ot taxa iast Highest priority genus within South Atrica not treated in any revisions revised pre-1970 tamily

Aizoaceae 1758 52% 12% Lampranthus J Hyacinthaceae 492 34% 11% Lachenalia Malvaceae 334 m 34% Anisodontea Ericaceae 944 13% 75% Erica Euphorbiaceae 387 12% 65% Clutia Asteraceae 2259 11% 33% Cyperaceae 438 11% 28% Cyathocoma Fabaceae t633 10% 15% Lessertia Asphodelaceae 568 9% 9% Astroloba Scrophulariaceae 802 8% 13% Microdon Geraniaceae 312 8% 5%. Pelargonium Acanthaceae 275 7% 33% Acanthopsis Rroteaceae 377 7% 19% Serruria Apocynaceae 675 7% 7% Emplectanthus Rutaceae 307 6% 49% ' Agathosma Iridaceae 1182 6% 5% Micranthus Crassulaceae 343 5% 0% Tylecodon , Poaceae 726 4% 1% Prionanthium 501 2% 0% Huttonaea Restionaceae 347 0% 0% Restio

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southern Africa and together represent more than 90% of the species flowering season, with the result that Marasmodes is poorly collected. diversity within Aizoaceae. Both these subfamilies have their centres Recently, eight new species were described based on existing herbarium ot diversity and endemism within two of South Africa's biodiversity material."' These new species are very poorly known, and are apparently hotspots -the Fynbos and Succulent Karoo Biomes.™ restricted to highly threatened lowland fynbos. A better understanding of Research priorities for the two subfamilies were set in the 1990s, the delimitation, distribution and abundance of all Marasmodes species when only 21% of taxa had been revised since 1940.^" Progress has is still needed, and would benefit greatly from field study, which is a been made, largely within the Mesembryanthemoideae where 75% matter of urgency as the last remaining fragments of lowland fynbos are of taxa have been revised recently enough to aid confident Red List rapidly disappearing. assessments. However, within the Ruschioideae, the largest subfamily South Africa's most studied large plant families are the Iridaceae, within the Aizoaceae, only 36% of taxa have been recently revised and 58% have never been revised. Conservation assessments are further Restionaceae, Poaceae and Orchidaceae (Table 1 ), and genera within these hampered by poor specimen representation in SANBI herbaria (74% ot families generally scored very low within overall priority ratings, with the taxa are known from five or fewer specimens) and low confidence in exception oiMlcranthus in the Iridaceae. For the complete list ot all genera specimen identifications (32% of specimens in PRECIS are not identified together with their priority scores, see Supplementary table 1 online. to species level or identified with uncertainty). A number of South Africa's largest plant genera are among the top 50 The Hyacinthaceae is another high priority, with 34% of taxa not yet research priorities (Table 3). However, not all large genera remain in revised, as a result of most of the family's largest genera such as need ot revision: 14 out of 35 genera containing more than 100 taxa Lachenalia, Albuca, and Drimia being only partly revised. In addition, have recent, comprehensive revisions, including two of South Africa's several conflicting name changes, published as part of molecular five largest genera: Aspaiathus (334 taxa) and Helichrysum (252 taxa). phylogenetic studies,^'-^^ have, in the absence of comprehensive Research needs are also not confined to larger genera; there are many revisions, led to great confusion over which taxa should be recognised, small genera that remain urgently in need of revision. Ot the 16 genera what their correct names are, and how they should be circumscribed. with no revisions, 13 have ten or fewer taxa occurring within South Africa, and most of these genera are endemic or near endemic to the The Ericaceae, Euphorbiaceae, Rutaceae, Malvaceae, Asteraceae and country (Table 4). Research needs within smaller genera are again Acanthaceae have lower proportions of taxa that are not revised, but linked primarily to the Aizoaceae subfamily Ruschioideae, with 12 of the all have more than 30% of taxa last revised betöre 1970 (Table 1). The tamily Ericaceae contains a single genus - Erica - which is South top 20 priority small genera found in this subfamily. Please see online Africa's largest plant genus with over 900 recognised taxa. This genus Supplementary table 1 for the complete list of research priorities. has its centre of endemism within the fynbos biodiversity hotspot and has a large number of highly range-restricted endemics. Erica was Taxonomic output synoptically revised in 1964-1965,^' but, with only an identification An analysis of outputs of taxonomic revisions for each decade since key and diagnostic characters provided for each taxon, this treatment is the 1960s indicates that revisionary research peaked in the 1980s insufficient for supporting conservation assessments. Only 11% o\ Erica and 1990s, but that there has been a sharp decline in the past decade taxa have been recentty revised in a number of partial revisions, and 124 (Figure 2). During the 1960s, most revisions of South African plants taxa (13% of the recognised taxa) have been described independentty were conducted by internationally based scientists, but since the 1970s, of revisions, with the result that 88% ot the genus is still in need of local researchers based at South African universities and SANBI have synthesis and revision. produced the majority of revisions. Independent local researchers, Within the Asteraceae, the fynbos endemic genus Marasmodes is often amateur botanists, have also made small contributions. During most urgently in need of revision. Only three taxa were recognised in the 1990s, South Atrican universities took the lead in local revisionary Fiora Capensis,^'' and a further two were described by 1946.^''"' Plants research, but all groups show a drastic reduction in published revisions within Marasmodes are cryptic, and flower outside the peak fynbos in the past 10 years.

6 000

5 000

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1960s 1970s 1980s 1990s 2000s

Figure 2: Number of South African plant taxa (species and subspecific ranks) revised in published taxonomic treatments per decade. Data is categorised according to the institutional affiliation of the senior author of each publication.

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There has been a steady increase in the number of individuai researchers for Calamophyllum, which is probably South Africa's most pooriy contributing to pubiished revisions ot South African piant taxa since known piant genus, vygies are generaiiy better represented in the Boius the 1960s, and oniy a siight apparent decrease in the past decade Herbarium (KiakC 2012, written communication, iVIarch 13), highiighting (Figure 3). However, at least eight researchers who contributed to the importance ot this collection for ongoing study ot the group. taxonomic revisions in the t990s are still employed as taxonomists in iocal and internationai research institutions, but did not publish in spite ot these chaiienges, the Aizoaceae are nevertheiess of high any revisions in the past 10 years, it they are inciuded in the number local research and conservation importance, not oniy because ot their of researchers, then there has been no deciine in the number of significant contribution to South Atrican tiorai diversity and endemism, taxonomists. instead, the data indicate a sharp deciine in the productivity but aiso because ot the insights they can provide into adaptations to an of taxonomists in reiation to their contribution to taxonomic revisions arid ciimate"^'"' and evolutionary drivers of high rates of speciation within since the 1960s, trom an average of 51 taxa revised per decade by a winter raintaii biodiversity hotspots."^ A strong researcii tocus on this taxonomist in the 1960s to only 20 in the 2000s. The decline is iinked plant tamiiy needs to be encouraged and ongoing studies on this group not oniy to a decrease in the number of pubiicatiors, but aiso to a rise shouid be given priority and sufficiency supported. in the proportion ot co-authored pubiications, from 8% in the t960s to As significant iong-term research investment is needed to study iarge 42% of pubiications in the 2000s, and smaiier numbers ot taxa revised genera, it is not surprising that many of South Africa's iargest piant per pubiication, trom an average of 29 in the 1960s to 18 in the 2000s. genera are stiii in need ot revision. Smaiier genera are presumabiy more attractive research subjects, particuiariy for short-term projects Discussion such as postgraduate studies, and theretore are expected to have better it is encouraging that 62% ot the South Atrican tiora has received recent revisionary coverage. Yet, in this study, 33 of the top 50 priority genera taxonomic revision, particuiariy considering the iarge number ot taxa. consist ot 10 or tewer taxa, and 25 ot these are endemic to South Atrica. However, with 19% (ca. 4000 taxa) ot the tiora without revision or not Smaii genera may be problematic in that they were often created to revised since the last publication ot Fiora Capensis, there is cleariy accommodate morphoiogicaiiy derived taxa, and phyiogenetic studies stiii much work to be done. The Aizoaceae tamiiy was highiighted as couid show that they are embedded in larger genera or even polyphyletic, a research priority already in 1995,^^ and, aithough some progress has but these results may aiso simpiy indicate a iack ot awareness ot genera been made, signiticant research efforts are still needed to address its requiring revision, and that there is a need tor a coordinated approach to iack ot taxonomic treatment, particuiariy tor the subfamiiy Ruschioideae. taxonomic research on the South African tiora.

Taxonomic study otthe Ruschioideae is challenging because otthe large Many examples ot iarge genera and tamiiies that have been compre- number ot species (approximately 1585 in 111 genera''^), many of which hensively revised (otten by individuai researchers), such as Aspalathus are poorly known,^^ and their very iow phyiogenetic resolution as a resuit (334 taxa by R. Dahigren), Helichrysum (314 taxa), the Manuieae ot their very rapid, recent diversitication."" For many type specimens, the (351 taxa) and Selagineae (233 taxa) tribes of the Scrophuiariaceae majority of which are housed in the Boius Herbarium at the University (by O.iVl. Hiiiiard), the Crassuiaceae (323 taxa by H.R. Tölken) and the ot Cape Town, intormation on where they were coiiected is iacking, Restionaceae (350 taxa by H.R Linder), have demonstrated that revision or they are trom cuitivated plants, which may differ significantiy trom ot large groups is not an insurmountabie challenge. For the production of wiid individuáis, making identitication with living populations difficuiL"^ Fiora of Tropical East Africa, over 75% of the 12 000 species treatments Genera in the Ruschioideae scored highiy in the priority setting anaiysis were compieted by oniy two taxonomists.'"^ not oniy because of a iack of revisions, but aiso because many species were represented by five or fewer specimens in SANBI herbaria and high The recent deciine in taxonomic research has often been blamed on proportions ot specimens cannot be identified to species ievei. Except the decline in the number ot taxonomists,'''^'"'" but our data indicate

160 80

140 70

1960s 1970s 1980s 1990s 2000s

I Number of researchers contributing to published revisions

•Average number ot taxa revised per researcher per decade

Figure 3: Changes in revisionary productivity over the past 50 years reflected as the number of individual researchers contributing to published revisions reiative to the number ot taxa (species and subspecific ranks) revised per researcher per decade.

Soutii African Journai of Science Volume 109 \ Number 3/4 http://www.sajs.co.za 55 March/April 2013 Research Article Taxonomy and conservation of the South African flora Page 9 of 10 that this is a false impression. Our results show that South Africa does under South Africa's Biodiversity Act {NEMBA Act 10 of 2004) to not lack the capacity to complete a comprehensive tlora treatment by coordinate and promote taxonomic research in South Atrica. Within 2020, but that a decline in revisionary productivity is the main stumbling this role. South Atrican taxonomists attending the SASSBX workshop block towards achieving this goal. A similar trend has been reported suggested that SANBI should provide leadership in strategically guiding internationally tor the publication ot descriptions ot new species across taxonomic research in South Atrica. It was also suggested that SANBI a number ot plant and animai groups, namely an exponential increase establish an electronic piattorm where existing taxonomic intormation in the number ot taxonomists contributing to new species descriptions, can be collated, and where taxonomists can contribute new content as coupled with a rise in co-authored pubiications, but a decline in well as curate existing intormation. Such a piattorm need not be limited individual productivity.'" These results introduce an alternative question to piants, but couid be made available to all taxonomic groups, as they in addressing the 'taxonomic crisis': why is taxonomic output in terms are likely to be tacing similar obstacles to publishing. ot revisions decreasing in spite ot increasing numbers ot taxonomists? However, merely providing electronic publishing infrastructure may not To investigate the reasons behind the decline in taxonomic productivity, a be enough to reverse the trend ot declining revisionary productivity. As workshop was heid at the tenth meeting ot the South Atrican Society tor the obstacles to publishing revisionary studies centre around a lack ot Systematic Biology (SASSBX) on 18 July 2012. Participants indicated sutticient credit tor ettort, a more challenging aspect ot developing an that taxonomic research has deveioped into a complex science where all e-taxonomy system would be to maintain scientitic credibiiity through possible species characters (inciuding molecular) need to be investigated peer review, as well as by providing a means to measure and reward in order to arrive at good delimitations ot species and genera, requiring impact, thereby giving researchers an incentive to contribute. It this more time-consuming, in-depth study, as weil as collaboration ot challenge can be overcome, aipha-taxonomic research could once again researchers with appropriate expertise in various analytical techniques gain ground as a highly esteemed and rewarding scientific discipline. to complete. A revisionary study requires the accumuiation ot what could amount to many years of research into a singie publication, which South Atrica is one ot tew countries that made good progress towards typically is not accepted by high-impact journais, nor does it receive achieving the GSPC 2010 targets.^" In order tor South Atrica to keep many citations. Academic pertormance assessment systems, however, up these high standards and tulfil our commitments to implementing demand a high publication output, and give less credit to multi-authored the GSPC 2020 targets, a strategic approach invoiving strong leadership publications. In addition, academic career advancement is achieved trom SANBI, as well as concerted ettort and cooperation ot the through publications in high-impact journals and high citation ratings. taxonomic community, wiil be needed. The current academic merit system theretore actively discourages the publication ot taxonomic revisions, by not giving researchers sutticient Acknowledgements credit tor the amount ot ettort required to complete such studies. This We, the gratetui users ot the products of taxonomic research but not situation also means that increased tunding and initiatives promoting taxonomists ourselves, thank Nicola Bergh, Benny Bytebier, John taxonomic research are unlikely to have the desired impact, as has been Donaldson, Michelle Hamer, Cornelia Kiak, John Manning, Dee Snijman, the case in South Atrica and around the world. Ben-Erik van Wyk, Tony Verboom and Janine Victor tor insighttui The consensus among the participants was that the best way discussion and comments on earlier drafts otthe manuscript, as well as forward would be to change to electronic publication, dissemination the participants ot the workshop held at the tenth meeting ot the South and curation ot taxonomic intormation, as has been the trend in the Atrican Society tor Systematic Biology. We also thank two anonymous internationai taxonomic community, tor example through projects such reviewers for suggested improvements. as Solanaceae Source and GrassBase.™ An interesting local example is the Restionaceae, one ot South Atrica's most well-studied large Authors' contributions plant tamilies (Table 1). This tamily was comprehensively treated in a D.R. was the project leader and contributed to writing the paper and conspectus published in 1985,^' and the treatment was updated in an research and data capture; L.V.S. designed and deveioped the database, electronic, interactive identitication key with descriptions and distribution analysed the data and contributed to writing the paper as weil as to the intormation pubiished on CD-ROM in 2001 .^^ The interactive key was research and data capture; A.D. was responsible tor the majority ot the subsequently published online, and kept up to date with a generic level research and data capture. reclassitication ot the Restionaceae as well as newly described species, with the latest version published in 2011.=^ This exampie illustrates References the etticiency ot the electronic publication tormat, which allows tor a 1. 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